Opening One Club

What Hands Do We Open One Club?

We can open 1♣!(16+ HCP, artificial, forcing) with any 16+ HCP hand. Balanced hands of 16 HCP or less are opened either 1♦ or 1N, depending on the chosen notrump range.

A flat hand should be downgraded 1 HCP, and a balanced hand with a decent five-card suit should be upgraded 1 HCP. We also use 1♣! to open “good” 15 HCP hands, defined as those with a 6+ card suit playable opposite a singleton, usually containing a singleton or void.

Opening 1♣ is unequivocally forcing. Responder must never pass, even with a club stack and no points.

Dealing with interference is covered later in Interference Over One Club.

One Club Responses By An Unpassed Hand

There is one “negative response”, 1♦!(0-7, artificial).

All other responses (“positive responses”) show 8+ HCP and are game forcing.

A three-suited hand is one that has three four-card suits, with any five-card suit being a minor. A three-suited hand with a very good five-card minor can treated as a suit. A three-suited hand with a five-card major should always be treated as a suit.

  • 1♥! shows any 8-11 HCP hand that is not three-suited.

    It says nothing about hearts or about shape, just HCP. See The One Heart Response.

  • 1♠! shows 12+ HCP, 5+ spades. Raising this to 2♠ is Beta.

  • 1N!, 2♣!, 2♦!, show 12+ with 5+ cards in the suit above. Accepting the transfer is Beta.

  • 2♥ shows 14+ HCP, balanced, no five card suit, forcing to 4N. 3♣ next asks for four-card suits up the line (Baron).

  • 2♠! shows a three-suited hand, 8-11 HCP. Opener bids 2N(relay) and responder shows the shortness using the 3x bids, below. See Three-Suited Hands.

  • 2N! shows 11-13 HCP, balanced, no five-card major; a good five-card minor is ok. This bid is forcing to 4N. Stayman is on. Other bids are natural.

  • 4N is plain Blackwood.

If a hand is not balanced and does not have a five-card suit, it is a three-suited hand.

  1. With a 12+ HCP three-suited hand, we bid it “submarine-style:”
    • 3♣! ♦ shortage
    • 3♦! ♥ shortage
    • 3♥! ♠ shortage
    • 3♠! ♣ shortage

No other response to 1♣! is permitted.

The negative response is discussed in the section The Negative Response.

The positive suit bids are discussed in the section Positive Responses.

The Three-Suited bids are discussed in the section Responding With A Three-Suited Hand.

Interference after a 1♣! opening is discussed in the next chapter, Interference Over One Club.

One Club Responses By A Passed Hand

By a passed hand, responses are similar:

  • 1♦! is negative (0-7)
  • 1♥! shows 8-10 HCP balanced.
  • 1♠ shows 5+ spades, 8-10 HCP.
  • 1N!, 2♣!, and 2♦ show the suit above, 5+ cards, 8-10 HCP.
  • 2♥, 2♠ show 4-6 HCP and a six card suit, HCP concentrated in the suit. Highly invitational.
  • 2N shows 11-12 balanced (a hand that we choose not to open 1♦).
  • 3x shows 8-10 three-suited hand short in x.

Responding With 11 HCP

There are two scenarios where a responder might have exactly 11 HCP:

  • A balanced passed hand with 11-12 HCP hand but responder chose not to open 1♦. This hand should respond 2N, showing a balanced 11-12 HCP.
  • Second, they are an unpassed hand. If they are unbalanced, the 2♠ (three-suited) reply applies, or 1♥. If balanced, bid 2N(11-13 HCP).

The One Diamond Response

After the weak 1♦(0-7 HCP) response, opener makes fairly natural bids designed to show his strength and shape. The Heart Relay allows us to show various strong balanced hands.

After 1♣! - 1♦!(0-7), opener’s rebids are:

  • 1♥! (hearts or 20+ balanced) describes a hand which is usually a heart suit but may also be a 20+ HCP balanced hand; or rarely, is 6-5 in the minors.

    See Heart Relay for the continuations.

  • 1♠, 2♣, and 2♦ show five card suits. These bids are non-forcing. If your hand has 8 tricks, do not make these bids.

  • 1N!(17-19, balanced)

  • 2♥! or 2♠! shows a strong hand with a 5+ card major, like a standard 2♣ opener followed by a 2M rebid.

  • 3♣ and 3♦ show very strong, unbalanced hands with a long minor suit.

  • 3♥ and 3♠ set trump and show an extremely strong hand (9 tricks). Trumps are long and solid. Partner should cue-bid.

  • 3N is to play based on a long solid suit.

Responder’s second bid:

  • With 0-4, pass, especially if balanced, unless you have an Ace.
  • Over 1♥, the heart relay is on, see below. If not playing that, treat as with 1♠.
  • Over 1♠, raise with 4-5 support points; jump raise with 6 or 7.
  • Over 1N, systems are on; see Balanced Hands for details.

The One Heart Response

1♣! - 1♥! is an artificial bid showing 8-11 HCP, any shape except three-suited. (When a passed hand, it is a balanced hand). Opener bids:

  • 2♣/♦/♥/♠ are natural showing five-card suits.

  • 1N (17-21 or 25+), systems on.

  • 2N (22-24)

  • 2♠ shows opener’s 3-suited hand, usually 4441, but sometimes (04)(45).

    Responder bids 2N!(shortness?), and opener bids the suit below the shortness, 3♠ for a club stiff. Responder sets his desired strain, giving precedence to a major, and opener raises to game, or artificially bids the next step up, starting Beta.

  • 3♣/♦/♥/♠ sets trump and is Beta.

It is quite common for opener to hide a five-card minor and bid NT instead.

Suit Responses

The response chosen shows the hand shape, and except for 1♠ are transfers to the next strain:

  • 1♣! - 1♠!(5+ spades)
  • 1♣! - 1N!(5+ clubs)
  • 1♣! - 2♣!(5+ diamonds)
  • 1♣! - 2♦!(5+ hearts)

These bids show 12+ HCP when made by an unpassed hand, 8-10 HCP by a passed hand.

These bids should be made with any five or more cards in a major suit. For a 5332 hand with a minor, we treat it as a notrump hand unless the suit is excellent, or the hand has 14+ HCP. Clubs in particular should almost always be a six-card suit since the 1N! transfer will wrong-side any notrump contract.

The auction is now game forcing. Then:

  • Opener bids responder’s suit; or,
  • Opener bids his own strain.

An opener with three-card support of a minor will often bid notrump or show a major suit first.

Opener Bids Responder’s Suit

Completing the transfer, or raising 1♠ to 2♠, shows support, and is Beta. Following the Beta response, a bid of trump asks the quality of responder’s trump suit, TAB. Any other suit bid is a control-asking bid, CAB, while a notrump bid or a game bid ends the asking sequence.

IMPORTANT: opener does NOT “super-accept” with a strong hand. Following the Beta response with a TAB or CAB or RKC shows slam interest.


1♣! - 2♦!(hearts, 12+ HCP)
2♥  - 3♣!(5 controls)
3♥ -  TAB in hearts

1♣! - 1N!(clubs, 12+ HCP)
2♣  - 2♥! (4 controls)
2♠!  - CAB for spades

--    Pass
1♣! - 1♠
2♠  - 3♣ (3 controls)

Opener had extras, so did not bid 4♠ immediately.

Opener Bids His Own Strain

If responder suggests a suit but opener does not accept, bidding continues naturally. Responder may raise opener’s suit, rebid his six-card or longer suit, bid a second suit of four cards or longer, or bid notrump.

If responder raises opener’s suit, opener can bid the next step as Beta, and subsequently use CAB bids in other suits.

Responder with support for opener’s suit may also choose a splinter bid if appropriate.

When opener bids NT, he does not jump, and systems are off. Responder can show a second suit of 4-cards, rebid his six-card suit, or raise NT.


1♣! - 2♦!(hearts)
2♠  - 3♥ (six hearts, < 3 spades)

1♣! - 2♦!(hearts)
2♠  - 3♠

1♣! - 2♦!(hearts)
2N  - 3♠ (hearts + 4 spades)
3N  - 4N (quantitative)

Balanced Responses

An unpassed balanced hand 8-11 HCP will respond 1♥, and if nothing else suggests itself after opener’s rebid, responder will bid NT to show his shape.

1♣ - 2N shows a balanced hand with 11-13 HCP. The hand does not contain a five-card major, but may contain a poor five-card minor. 3♣ is Baron, asking for four-card suits up-the-line, but may have clubs.

1♣ - 2♥ is the strongest balanced response, showing 14+ HCP and no five-card suit, forcing to 4N. If opener bids NT, Stayman but not transfers are on.

Responding With A Three-Suited Hand

If responder does not have a five-card suit, and is not balanced, then he usually has a 4441 shape. (Holding a mediocre five-card minor such as 4=0=4=5, you might choose to treat it as a three-suited hand rather than the minor suit.)

The Two Spade Rattlesnake Bid

With an ordinary three-suited hand, an unpassed hand bids 2♠! over 1♣!. This shows 8-11 points and is game forcing.

Opener bids 2N asking which suit has the singleton. Responder bids the singleton submarine using the 3x bids and the auction proceeds along the lines below.

When opener has a 0=4=4=5 or 1=3=4=5 shape, the auction would go 1♣ - 1♥ - 2♠ - 2N - 3♥ and responder can place the contract. If the clubs are not great, and the hand is minimal, a 2♠ response may be preferable to the 2♣ response.

The Three-Suited Bids

When a three-suited has 12+ HCP, or 8-11 HCP by a passed hand we “submarine” the shortage:

  • 3♣ diamond shortage;
  • 3♦ heart shortage;
  • 3♥ spade shortage; or,
  • 3♠ club shortage.

When responder has shown a 12+ HCP hand, they may be interested in slam even when opener has a minimum. Therefore, we want a scheme in which opener places the contract, leaving responder free to bid on. With a 12+ responder, the auction should be treated as forcing to 3N, 4M, or 5m.

Opener’s rebid shows his strength:

  • If the opener has slam interest, he can set trump by first bidding one of the four-card suits as ETA. After ETA, side-suit bids are CAB, 4N is RKC. Bidding trump is a sign-off.
  • If the opener has a minimum 16-19, opener bids the shortage suit. This says, “I’m a minimum, no slam interest from my side.” Responder now relays the next step up. Opener then bids his desired contract.
With a 12+ HCP hand and extras, responder can then answer opener’s desired contract
as ETA, with opener’s choice being trump, or make an appropriate quantitative raise in NT.

When There Is No Major Fit

If opener does not have a major fit, possible final contracts are in notrump, a minor, a 4-3 fit in a major, or the stiff suit itself at the four-level or higher. Notrump is only possible with a stopper(s) in the shortage suit.

When the shortage is not clubs, a minimal opener has room to bid the stiff and then choose a strain. However, when the shortage is clubs, there is a problem since bidding 4♣ would skip over 3N, which might be a desired final contract. So:

  • With a club stopper opener may bid 3N. Responder without slam interest should pass 3N.
  • Without a club stopper, bid 4♣. Responder should bid 4♦, which opener can pass if responder is 8-10, raise to 5♦, or choose a 4-3 fit in a major.

When Responder Bids On

When responder has 14+ HCP or a source of tricks, he can bid on, but opener’s choice of suit or notrump is final. Bidding 4N is quant or keycard respectively. Responder can bid the stiff to suggest slam if there are no wasted values in the stiff suit.